Network switches (also known as switching hubs, bridging hubs, MAC bridges or simply “switches”) are computer networking devices that connect other devices together in a computer network. Network switches are typically used in complex data networking environments to, for example, interconnect various devices within one or more sub-networks. Some network switches use packet switching to receive, process, and forward network traffic to destination devices. Switches can be used for electrical switching, optical switching that enables signals in optical fibers or integrated optical circuits to be selectively switched from one circuit to another, or a combination of electrical and optical switching.
Typical network switches include multiple circuit boards with associated switch elements (e.g., line cards and fabric controller cards) that are interconnected via backplane or midplane circuit boards within an enclosure. The line cards typically include a modular electronic circuit designed to fit on a separate printed circuit board (PCB) and interface with a data communications network, and can provide transmitting or receiving ports for a local area network (LAN) and/or a wide area network (WAN). Each line card includes one or more switch elements to transmit or receive network traffic. Fabric controller cards can include one or more switch elements for implementing stages of the switch fabric. The line cards and fabric cards can be mounted to the backplane or midplane in a motherboard /daughterboard relationship in which the backplane or midplane extends transversely across the enclosure of a network switch. It would be advantageous for a network switch to implement a less complex configuration of switch elements that improves performance.